Method of cutting bars from centrifugal castings



5W. 23 m4., www? K. A. SODERSTROM METHOD OF yCUTVTlNG BARS FROM GENTRIFUGAL CASTINGS Filed April 17. 3.923 2 Shes-Sheet l Sept. 23, 1924. 1,509,617

K. A. 'SODERSTROM METHOD vOF CUTTING .BARS -FROM CENTRIFUGAL CASTINGS Filed April 17. 1923 2 Sheets-Sheet 2 cutting bars from centrifugally cast shellsuct.

Patented Sept. 23, 1924.

11,509,617 PATENT! oFFicE.

KARL A. SODERSTROM, '0F PHILADELPHIA, PENNSYLVANIA.

METHOD 0F CTTING BARS Y.FROM CENTRIFUGAL CASTINGS.

Application filed April 1.7, 1923. Serial No. 632,716. I

To all whom it may concern.:

Be it known that I, KARL A. SoDERsTRoM, a citizen of theUnited States, residing-'at Philadelphia, county of Philadelphia, and

State of Pennsylvania, have invented a new and useful Improvement in Methods" of Cutting Bars from Centrifugal Castings, of

which .the following is a full, clear, and exact description, reference being had tothe accompanyi-n drawings, which form a part of this speci cation.

My invention relates to a novel method of or ingots.

In the manufacture of various products of steel, it isfound desirable to have the carbon content vary throughout the prod- For example, in a steel rail, it is desirable that the head of the rail be relatively high, in carbon, while'the foot may be relatively low in carbon. In the manu facture of plow shares, it is desirable to leave one face of theshare high in carbon and the other face .relatively low in carbon, which is at present effected by forming'the share of two plates, one of relatively liigli carbon and the other of relatively low carbon, secured together. Y Y l Further, in the Imanufacture of sprin s, it is found desirable that one portion'of t e spring be higher in carbon than another.

Now it is the object of 1n invention to provide a methodl wliereb ars or billets may be produced which wi 'l enable the production of articles having var ing carbon content. More particularl it 1s the 0b]ect of my invention to provide a method of v producing bars, lwherein the carbon content varies, from centrifugally cast shells or ingots. l

Having now indicated in a general way the nature, purpose and advantages of my invention, I will now proceed to a detailed description thereof with reference to the accompanying drawings, in which: p

Fig. 1 is a diagrammatic view of av centrifugal casting apparatus with a casting therein.

Fig. 2 is a diagrammatic view of a cutter and supporting roll in 0 erative relation to a centrifugally cast Shel l Fig. 3 is a diagrammatic view of apparatus for spirally cutting a shell and straightening a spiral.

Fig. 4 is a cross-sectional view of a bar for forming a rail.

' Fig; 5 isa cross-sectional view of a bar for forming'a spring leaf.

Fig. 6 is, a cross-sectional view 'of a plate for forming a plow share.

a represents a centrifugal-mold provided with top and bottom `covers b, b formedy so a's 'to produce a shell or casting c having formed at its ends an abruptly stopped spiral, as indicated at d. The mold is adaptedl to be vsupported for rotation by means of a fly wheel e in engagement with a friction'ring f on the mold.

The shell or casting c is formed in the mold under the influence of centrifugal force, and its composition, so far as carbon content isconcerned, varies from a relatively high carbon content adjacent the inner face of the 'wall of the sirelhto a relatively low carbon content adjacent the outer face'of the wall, the intermediate portion varying in carbon content from the maximum to the minimum. In Fig. 1 I have in? dicated the zone of relatively high carbon by the letterY g, the zone of relatively low carbon by the letter h, and the intermediate zone bythe letter z'.

In accordance with my method, the shell or casting c, after having been cast, is removedifrom the mold a and one of its ends supported upon a supporting roll 'j mounted upon a shaft lc and provided with an end ange l adapted to enga e the end ofthe adapted to engage the abruptly stopped' spiral formed on the end of the shell and out they shell spirally` from'end to end.. The shaft c ofthe supporting roll may be driven throughsuitable gears from a shaft o, which in turn' is driven through a ring gear p.

The shaft n is supported at one end by a bracket other end strap 8 pivotally secured to a bearing t. The shaft n is driven by means of a ring gear p and as will be observed may be swun on the shaft r to enable adjustmentl of t e cutter.

The spiral u cut from the shell is received between guide v and guided between a pair of rolls w, which act to straighten and shape `vthe spiral to produce a bar for the fabrig pivoted on shaft r and at the l ing the spiral, a bar is produced having differential carbon content and from which may be produced rails having a high carbon head and a relatively low carbon foot. It will be obvious that such a bar will lend itself to the fabrication of a plow share having one face of high carbon and the other face of low carbon, thus avoiding the necessity of the use of two plates.

It will be obvious that my invention is not limited to any particular use of the bar produced,` as many uses therefor will commend themselves.

Havin now -fully described-my invention, what I c aima-nd desire to protect by Letters Patent is:

l. The method of producingbars con-l sisting in spirally cutting a centrifugally cast hollow ingot.

2. The method of producing bars consisting in spirally cutting a centri'r'ugally cast hollow ingot and straightening the` spiral, all while the metal is vin a heated condition. i

' 3. The method of produc-ing steel hars 4. The method of producing steel bars having a relatively high carbon content adjacent one surface and a relatively low carbon content adjacent the opposite surface consisting in spirally cuttin a shell formed by centrifugally casting car n steel.

5. The method of producing steel bars having a relatively high carbon content adja- 1 cent one surface and a relatively low carbon content adjacent the opposite surface consisting in centrifugally casting a shell of carbon steel, removing the shell from the'mold, and spirally cutting the shell.

`6. The method of producing steel bars having a relatively high carbon content adjacent one surface and a relatively low carbon content adjacent the opposite surface consisting in forming a cylindrical shell having an'abruptly stop ed spiral at one end, spirally cutting thes ell, and straightening the spiral.V

-7. The method of producing articles having a differential carbon content consisting in centrifugally casting a shell, spirally cutting the shell, straightening the spiral to form a bar, and working the bar to producecthe article.

In testimony of which invention I have hereunto set my hand, at Pittsburgh, on this twelfth day of April, 1923.

A KARL A. SODERSTROM. 

